1. Field of the Invention
The present invention relates to the field of the study of materials subjected to very high temperatures, notably in a degrading atmosphere.
2. Description of the Prior Art
Industrial equipments working under high temperatures (above 200° C.) are frequently subjected to environments likely to cause corrosions and degradations of the materials they consist of, and depositions on the surface thereof. In order to ensure reliability of these equipments, it is necessary to control these phenomena such as: oxidation, sulfurization, carbonizing, metal dusting, nitriding, hydridation, chlorination, molten salt attack, and combinations of these degradations. The deposits likely to form on the equipment walls are notably: carbon-containing products (coke), molten salts, volatile compound condensations.
In order to select suitable materials and to monitor their behavior, thermogravimetric analyses (TGA) are commonly used. These analyses are carried out in specific devices referred to as thermobalances, where the conditions of the industrial environment are reproduced to allow continuous determination of the evolution of the mass of a material sample as a function of time.
Acoustic emissions were used so far to control the generalized and localized corrosion of metallic materials immersed in electrolytes. Some studies (“F. Ferrer, J. Goudiakas, E. Andres and C. Brun, Nace Corrosion 2001 Conference, Paper 01386”; and “M. Schulte, A. Rahmel and M. Schutze, Oxidation of metals, 49 (1998) 33”) tried to use large acoustic emission detectors to evaluate the behaviour of tube sections in pilot plants.
The present invention relates to a device comprising a specific thermobalance allowing to measure, together with the mass variation of the sample, acoustic signals emitted by the sample. The information, compared, recorded and subjected to real-time processing, allows to optimize the material behavior analyses and to simplify industrial monitoring thereof, notably by means of an analysis of the phenomena kinetics.